Gran'ma Wood's Chocolate Prune Cake

2 cups cooked prunes

2/3 cup shortening

1 ½ cup sugar

3 eggs, well beaten

1 teaspoon vanilla

4 teaspoon baking powder

½ teaspoon soda

½ teaspoon salt

2 squares (2 oz.) bitter chocolate

2 ¾ cup cake flour

1 cup milk

Pit prunes and cut into small pieces.  Cream shortening and sugar thoroughly.  Melt chocolate over hot water and add to creamed mixture;  mix.  Add well-beaten eggs and mix again. 

Sift flour with baking powder, soda and salt, and add alternately with the milk, a small amount at a time.  Add prunes and vanilla band beat thoroughly.  Pour into 3 greased layer cake tins and bake 25 to 30 minutes in a moderate oven 350° or 375°.  Put layers together and spread top and sides with chocolate butter frosting.